Saw chain cutter



May 29, 1956 J, B, cox 2,747,623

SAW CHAIN CUTTER Filed May 26, 1953 INVENTOR.

JOSEPH B. COX

ATTORNEYS United States Patent ICC 2,141,623

SA-W CHAIN-CUTTER Joseph. B. Cor, Portland, reg;, assignor, by mesne assignments; to= OreggmSdw-Cliaih Corp a corporation of oi'egon Application :May 26, .1953, ,Serial N0. 35.-7,526

The. present: invention relates tit-saw.- chains and,while they are. particularly: designed fon use in; cutting; wood, it will become. apparent as. the description: proceeds. that the. sawchains of. the present invention are-also; adapted for cutting minerals, and other. materials The. most commontorm of sawchains. as used. heretooth-whichcuts'theside wall. ofthe;ke1=f and the;tooth will. tendtogouge outwardly inthe directionof the, 03% set. As. a: consequence, as saw chain; madeup; of. such teeth;will.be-inherently rough or jerky inoperation, causing, the operation of thesawto he. fatiguing; upon the-,op-

erator and also causing rapidiwear upon; the various parts ofithechainand the: saw. These: disadvantages are over come with the present, invention: providing; a; full kerf width cutting element.

A, primary object. of, the. present; invention is, to; provide a saw chain whichzhas an-inherently smooth: action, r6duCing operator. fatigue.- and wear,- on. the: chain. saw- Another object of the invention:isfto provideanew and improved. saw chain; in which eachacutting tooth in; itself is. completelyoperative-to slicea shaving; from thebottorn of the kerf.

A further objectrof the.- present iJlFT/llfiflfliiS iOsPfOF/idfi a cutting tooth; of. such. configuration. that. the :load; thereon is substantially. balanced. on the; opposite; sides. of the medianplaneof the tooth,

A still-further, object of the, inyentionis theprovision of a. new'and improved cutter elemfintfon sawchainsin whicheachcutter element. seversa shaving from, the; bottom: of the kerfthroughont the full'width thereof.

Other objects. and advantages. of the. invention will become more apparent hereinaften.

In; accordance. with. an; illustrated embodiment, the present invention comprisesa. Urshaped. saw chain cutter toothelement having ,a..pair, ofspaced apart kerfside. wall cutting, edge. defining. portions and. a. kerf. bottom cutting edge. defining portion, extending, therebetween. The. op.- positekerfiside wall cutting edges. are spaced. apart. longitudinally offthe element, an d the-kerfbottom cutting edgeextends therebetween. at an obliqueangle transversely of the element. whereby the. elemntwill smoothly slice a shaving fromthe bottom ofa kerfthroughout substantially;thefullfwidththereof.

For a consideration of what is believed, novel and inventive, attention is directed to the following; description of certain embodiments taken in connection, with the accompanyingdrawingsg whilefeatures of novelty will be; pointed? out in greater particularityinthe appended claims:

Patented May 29, 1956 Referring now' to the dra-wingsz Fig. 1. is a side: elevation of a portion of, asaw chain constructed in, accordance with one: form-of the present invention;

Fig. 2 is atop plan view' ofthe. chain in Fig. 1;

Fig. 3. is an enlarged front elevation-of. aportion of a saw chain link ofthe. invention illustrating the samein relation to a kerf in a workpiece;

Fig. 4 is a cross-sectionalview of a link takenalong line4.-4.of;Fig, 3;

Fig. 5 is a cross sectional view taken along; line 5-5 of Fig; 3 and Fig. 6 is. a perspective view -illustr-ating a saw according to a modification of the. invention.

Referring now'to Fig, l, a saw chain oftthe invention comprises a pluralityofcentrally; disposed, longitudinallyspacedeapart alternate cutter linkslltand spacer-linksli; The cutter links 1i) andspacer links. 11 are connected-together by means of pairs; of intermediate side. plates 14 disposed on. opposite sides ofthelinks: and: ivotallyasecured thereto bymeansofiv rivetslfi. The spacer. links-1d. include a sprocketengaging root-12 depending. fromith'e lower edge thereof, which portion-is adapted to slide with..- in the groove. of thesaw bar ofjachain saw The'cutter links ill-each comprise; a. body element. or portion-17 and a cutter tooth elementor; portion;v 1%. Thebody portion 17- alsohas a sprocket and-saw: bar groove. engaging ro'ot 12 depending from thelower edge thereof;

Referring now morev particularly to Figs.- 3, 4 and 5, the cutter elementel includes; asubstantially flat, elongate base portion 23'which extends laterally on eaclr of the opposite sides of the. body portion 17 a. substantially equal distance; IntegraL withv the oppositeside edges of the base 23, and extending upwardly therefrom and slightly diverging symmetrically from the. plane. ofthe body portion 17, area pair of: relatively short;. laterally spaced apart kerf sidewall cutting edge. defining v portions or walls 26, 27- whichare; spaced substantially equidis: tantly on opposite sides of the longitudinal centerv line-or median plane of the. chain indicated at 39- in. Fig. 3. Extending; between the-ends of the cutter side walls 26, 27 and; integral, therewith, isa kerf bottom cutting: end wall 28, the central part of: which extends; substantially parallel to the base 23, while the opposite corners orside partsv thereot form a; smooth curved juncture with. the respective cutter side walls. A. hollow arched; on U. shaped cutterlink is thus formed which is symmetrically disposed'in respect to. the. median plane of thechaim. As more clearly seen in Fig; 4,, the: cutter side walls; 26; 27 are longitudinally spaced-apart along the chain sothatithe leading edge of one of the walls 26 is advanced imrespect to the other wall 227. Preferably, the; cutter: side wall spacing and lengthis: such: that the leading, side wall; 26 iswholly spaced ahead of. the; forward edge 1 of. the: other cutter sidewall 27 by.- a distance substantially equal; to thelength of the, side walls; the reason for which will become apparent. hereinafter. Theleadingedge. of" the cutter end wall 23 extends in a substantially straightline between the leading edges; of the side, walls 26 27 and at an.-oblique angle of. about/15 degrees in the. direction transversely. of the. cutter tooth. element. Formed in;- tegrally with the forwardeend of: the cutterelement lfisissa depth gauge 35' ofiset laterally. from the planeof the body portion 17 towardithe sideof the leading. cutter side wall 26 a distance slightlyless than the. distance. ofotfset of the side walls, the rear edge 36 of thedepth. gauge.35 being spaced ahead of the forward edge offthe leading sidewall 26 by the'arcuate recess 37.

As viewed'rnostclearly in Fig, 3, it will beobserved that, in addition to the encLwall'Zli, only the uppermost portions of-the" cutterside walls 26, 27 are provided with a cutting'ed'ge, which" portions extend, however, below 3 the top surface of the depth gauge 35. This configuration will enable a tooth to completely sever a shaving 33 (Figs. 3, 4 and 5) from the bottom of the kerf, but will 7 minimize the length of edge which might gouge intothe posed on each tooth will be substantially balanced in re- 'spect to the longitudinal center line thereof, and the teeth will tend to proceed in a straight line through the kerf without gouging into' the side walls of the kerf, which would cause a useless expenditure of energy in any case,

and in some instances might even cause the chain to stall. The slanted cutting edge on the teeth will cause them to cut the wood fibers with a slicing action which maybe accomplishedwith less effort than would be required if the cutting edge were disposed at right angles to the direction of travel of the tooth, in which latter case the sever ing' action would be more in the nature of a wedgiug operation requiring considerable energy. The longitudinal displacement of the side walls 26, 27 in accordance with the preferred embodiment is of advantage because of the large opening thus provided through'which the v spiraling chip 353 may pass freely.

In the perspective view of Fig. 6 is illustrated a modified '7 cutter tooth link 4% which may be substituted for the cutter links of the saw chain as previously described. Whereas the cutting edge defining portion 18 of the links it is flat across the end, the present cutting edge defining portion 41 is rounded, the arc of the bight of the element being'substantially a section of a circle. As in the modi fication described previously, the leading edge 42 :ot the 'cutter'element 4t isinclined with respect to the direction ofitravel of the saw chain and is provided with a sharp, chisel edge. 7

T he cutter elements of the present invention may readily be made economically as by an investment casting process, the only finishing operation required being a slight grinding on the outer surfaces to perfect the cutting V edges.

" Having illustrated and described preferred embodiments of the invention, it should be apparent to those skilled in the art that the'invention permits of further modification in arrangement and detail. I claim as my invention all such modifications as come within the true I claim: V a 1 r 1. An elongate saw chain cutter tooth element having a pair of spaced-apart kerf side wall cutting edge defining portions and a kerf bottom cutting edge defining portion joining said side wall cutting edge defining portions, said side wall cutting edge portions being offset with respect to each other in the direction longitudinally of the element.

2. In a saw chain, a plurality of cutter links, each of spirit and scope of the'appended claims.-

' said cutter links comprising a pair of kerf side wall cutting portions spaced laterally on opposite sides of the median plane of said chain a substantially equal distance, the leading edges of said side wall cutting portions being spaced apart longitudinally of said chain, and a kerf bottom cutting portion extending between said kerf side wall cutting portions.

3.1A saw chain comprising a plurality of cutter links edge defining portion extends at an oblique angle in the direction transversely of the element.

5. A saw chain cutter tooth element according to claim 1 in which the outer surfaces of all of said portions are flat.

6. A saw chain cutter'toothelement according to claim 1 in which the side wall cutting edge portions diverge with respect to each other in the direction towardsaid kerf bottom cutting edge defining portion. V

7. In a saw chain, a link'comprising a pair of longitudinally spaced-apart kerf side wall cutting portions. and a kerf bottom cutting portion integral therewith, said kerf side wall cutting portions being disposed on opposite sides of the longitudinal median plane of said saw chain and diverging symmetrically therefrom toward said kerf bottom cutting portion.

8. in a saw chain, a cutter tooth element comprising a pair of kerf side wall cutting edge defining portions spaced apart longitudinally of the chain and a kerf bottom cutting edge defining portion integral therewith, said kerf side wall cutting edge defining portions being symmetrically disposed on opposite sides of the longitudinal median plane of said saw chain and diverging therefrom towards said kerf bottom cutting edge defining portion, the central part of said kerf bottom cutting edge defining portion lying in a plane normal to the longitudinal median plane of said saw chain, the opposite side parts of said kerf bottom cutting edge defining portion being curved to the juncture thereof with said side wall cutting edge defining portions. Y

9. An elongate saw chain cutter tooth element comprising a pair of laterally and longitudinally spaced-apart kerf side wall cutting edge defining portions and a ke rt bottom cutting edge defining portion integral therewith,

said kerf side wall cutting edge defining portions being symmetrically disposed on opposite sides of the longitudinal median plane of said element, the opposite side parts of said kerf bottom'cutting edge defining portion being curved to the juncture thereof with said kerf side wall cutting edge defining portions to' form a hollow, arched element, the cutting edge of said kerf bottom cutting edge defining portion-extending at an oblique angle in a direction transversely of the element.

10. A saw chain link including a body portion having a planar saw groove engaging root and a cutter tooth element having a planar base portion extending substantially equal distances laterally on the opposite sides of said root, said cutter tooth element including a portion substantially U-shaped in cross-section to provide legs terminating at the sides of said base portion, the leading and trailing edges'of said U-shaped portion being substan-" tially parallel and extending at an oblique angle the median plane of said chain so as to space said legs longitudinally along said base portion, said leading edge having a sharp chisel cuttingedge formed thereon, the foremost distances laterally on the opposite sides of thelongitudinal central median plane of said' chain, said cutter tooth said base, the arcof the bight of said portion bein'gsubr stantially a section of a circle, the leading and trailing edges of said portion being inclined obliquelysaid median plane so as to space said legs longitudinally along .said

base, said leading edge having a sharp. chisel cutting edge thereon, the foremost of said legs being spaced wholly forwardly of the trailing l eg whereby to provide a large opening through which severed chips may pass.

12. Ina saw chain; a hollow cutter link comprising a pair of laterally and longitudinally spaced-apart k'erfside ll. In a saw chain, a link including a cutter tooth element having a planar base extending substantially equal wall cutting portions and a kerf bottom cutting portion integral therewith, said kerf side wall cutting portions being symmetrically disposed on opposite sides of the longitudinal plane of said saw chain, and a depth gauge integral with the leading end of said link, said depth gauge being offset laterally from said longitudinal plane on the side of the foremost side wall cutting portion a distance slightly less than the longitudinal spacing of said side wall cutting portions.

13. In a saw chain, a link including a cutter tooth element having a planar base extending substantially equal distance laterally on opposite sides of the longitudinal median plane of said chain, said tooth element including a portion substantially U-shaped in cross-section to provide legs terminating at the sides of said base, the leading edge of said portion being inclined with respect to said median plane so as to space said legs longitudinally along said base, said leading edge having a sharp chisel cutting edge thereon, and a depth gauge integral with the leading end of said link, said depth gauge being offset laterally from said medium plane on the side of the foremost leg a distance slightly less than the longitudinal spacing of said legs.

References Cited in the file of this patent UNITED STATES PATENTS 2,508,784 Cox May 23, 1950 2,534,591 Geurian Dec. 19, 1950 2,558,678 Garrett June 26, 1951 2,622,636 Cox Dec. 23, 1952 2,655,958 Gommel Oct. 20, 1953 

